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package com.tlf.dyjc5.filter;

import java.io.IOException;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.io.StringWriter;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.dusin.web.util.JsonUtil;

/**
 *
 * @author tengyu
 */
public class QXFilter implements Filter {

    private static final boolean debug = true;
    // The filter configuration object we are associated with.  If
    // this value is null, this filter instance is not currently
    // configured. 
    private FilterConfig filterConfig = null;

    public QXFilter() {
    }

    private void doBeforeProcessing(ServletRequest request, ServletResponse response)
            throws IOException, ServletException {
        if (debug) {
            log("QXFilter:DoBeforeProcessing");
        }

        HttpServletRequest req = (HttpServletRequest) request;
        HttpServletResponse res = (HttpServletResponse) response;
        
        String url = (String) req.getRequestURI();
        String s = req.getContextPath();
        String loginName = (String) req.getSession().getAttribute("user");
        if ((loginName == null || "".equals(loginName))&&!url.equalsIgnoreCase("/DYJC5Web/servlet/home/LogoutServlet")) {
            if(url.endsWith("Servlet")||url.endsWith("Del")||url.endsWith("Save")||url.endsWith("Load")||url.indexOf("servlet")>0){
                response.setContentType("text/html;charset=UTF-8");
                PrintWriter out = response.getWriter();
                //req.getRequestDispatcher(s+"/sessiontimeout.jsp").forward(request, response);
                //res.sendRedirect(s + "/sessiontimeout.jsp");
                try{
                    out.println(JsonUtil.createFailureJsonResponse("您还没有登陆或者Session已过期"));
                }finally{
                    out.close();
                }
            }else{
                res.sendRedirect(s + "/sessiontimeout.jsp");
            }            
        }        
    }

    private void doAfterProcessing(ServletRequest request, ServletResponse response)
            throws IOException, ServletException {
        if (debug) {
            log("QXFilter:DoAfterProcessing");
        }
    }

    /**
     *
     * @param request The servlet request we are processing
     * @param response The servlet response we are creating
     * @param chain The filter chain we are processing
     *
     * @exception IOException if an input/output error occurs
     * @exception ServletException if a servlet error occurs
     */
    public void doFilter(ServletRequest request, ServletResponse response,
            FilterChain chain)
            throws IOException, ServletException {

        if (debug) {
            log("QXFilter:doFilter()");
        }

        doBeforeProcessing(request, response);
        HttpServletRequest req = (HttpServletRequest) request;
        HttpServletResponse httpResponse  = (HttpServletResponse) response;
        //System.out.println( req.getHeader("Referer"));
        //httpResponse.setHeader("X-Frame-Options", "SAMEORIGIN");   //前台改造，暂时注释掉
        //System.out.println((String) req.getRequestURI());
        Throwable problem = null;
        try {
            chain.doFilter(request, response);
        } catch (Throwable t) {
            // If an exception is thrown somewhere down the filter chain,
            // we still want to execute our after processing, and then
            // rethrow the problem after that.
            problem = t;
            //t.printStackTrace();
        }

        doAfterProcessing(request, response);

        // If there was a problem, we want to rethrow it if it is
        // a known type, otherwise log it.
        if (problem != null) {
            if (problem instanceof ServletException) {
                throw (ServletException) problem;
            }
            if (problem instanceof IOException) {
                throw (IOException) problem;
            }
            sendProcessingError(problem, response);
        }
    }

    /**
     * Return the filter configuration object for this filter.
     */
    public FilterConfig getFilterConfig() {
        return (this.filterConfig);
    }

    /**
     * Set the filter configuration object for this filter.
     *
     * @param filterConfig The filter configuration object
     */
    public void setFilterConfig(FilterConfig filterConfig) {
        this.filterConfig = filterConfig;
    }

    /**
     * Destroy method for this filter
     */
    public void destroy() {
    }

    /**
     * Init method for this filter
     */
    public void init(FilterConfig filterConfig) {
        this.filterConfig = filterConfig;
        if (filterConfig != null) {
            if (debug) {
                log("QXFilter:Initializing filter");
            }
        }
    }

    /**
     * Return a String representation of this object.
     */
    @Override
    public String toString() {
        if (filterConfig == null) {
            return ("QXFilter()");
        }
        StringBuffer sb = new StringBuffer("QXFilter(");
        sb.append(filterConfig);
        sb.append(")");
        return (sb.toString());
    }

    private void sendProcessingError(Throwable t, ServletResponse response) {
        String stackTrace = getStackTrace(t);

        if (stackTrace != null && !stackTrace.equals("")) {
            try {
                response.setContentType("text/html");
                PrintStream ps = new PrintStream(response.getOutputStream());
                PrintWriter pw = new PrintWriter(ps);
                pw.print("<html>\n<head>\n<title>Error</title>\n</head>\n<body>\n"); //NOI18N

                // PENDING! Localize this for next official release
                pw.print("<h1>The resource did not process correctly</h1>\n<pre>\n");
                pw.print(stackTrace);
                pw.print("</pre></body>\n</html>"); //NOI18N
                pw.close();
                ps.close();
                response.getOutputStream().close();
            } catch (Exception ex) {
            }
        } else {
            try {
                PrintStream ps = new PrintStream(response.getOutputStream());
                t.printStackTrace(ps);
                ps.close();
                response.getOutputStream().close();
            } catch (Exception ex) {
            }
        }
    }

    public static String getStackTrace(Throwable t) {
        String stackTrace = null;
        try {
            StringWriter sw = new StringWriter();
            PrintWriter pw = new PrintWriter(sw);
            t.printStackTrace(pw);
            pw.close();
            sw.close();
            stackTrace = sw.getBuffer().toString();
        } catch (Exception ex) {
        }
        return stackTrace;
    }

    public void log(String msg) {
        filterConfig.getServletContext().log(msg);
    }
}
